Electric switch.



No. 788,980. PATENTED FEB. 28, 1905.

' W. H. POWELL.

ELEGTRIG SWITCH.

APPLIOATION FILED 001.24, 1904.

T-II -I. l Z I] 1? Witnesses=. Inventor,

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of the drum type, wherein a series of contacts UNITED STATES Patented February 28, 1905.

PATENT OFFICE.

WILLIAM H. POWELL, OF EAST ORANGE, NEWV JERSEY, ASSIGNOR TO OROOKER-l VHEELER COMPANY, OF AMPERE, NEIV JERSEY, A COR- PORATION OF NEW JERSEY.

ELECTRIC SWITCH.

SPECIFICATION forming part of Letters Patent No. 783,980, dated February 28, 1905.

Application filed October 24, 1904. Serial No. 229,740.

To ctZZ 107L071), it nuty concern:

Be it known that I, WVILLIAM- H. PownLL, a citizen of the United States of America, and a resident of East Orange, county of Essex, State 5 of New Jersey, have invented certain new and useful Improvements in Electric Switches, of which the following isa specification.

My invention relates to the construction of the movable member of an electric switch lie on the surface of a cylinder which is 1 volved under contact-fingers to eflect the desired changes in the electrical connections.

One object of the invention is to afford a 5 simple and durable construction for the switchdrum, dispensing with a wooden core, which has heretofore been employed in the construction of switches of this general type, and utilizing drawn steel rods, which occupy side positions in the drum as supports for the rings.

Another object of the invention is to provide for the convenient removal and replacement of any part without the necessity of removing other contact-carrying parts, the con- 2 5 tact-rings being in two parts or semirings and so engaging with the side rods that each can be removed without the removal or disturbance of other semirings.

1n the accompanying sheet of drawings,

3 which form a part of this application, Figure 1 is an elevation of a switch-drum embodying my invention in which the contacts are arranged for motor control by multiple-voltage changes and field regulation and for reversal.

gyFig 2 is an end view showing the star-wheel.

Fig. 3 is a section through the drum on the line III III of Fig. 1, showing the ring which carries the contacts for field variation. Fig. 4 is asection through the drum on the line 4 TV IV of Fig. 1 through the rings for effecting reversal and multiple-voltage changes, each of these rings being substantially the same in plan view. Fig. 5 is a development of the drum, to which is added a diagram of the electrical connections from the controller to multiple-voltage leads and to an electric motor.

The lnventlon as herein illustrated 1s embodied in a drum for an electric-motor controller of the multiple-voltage type, such as is set forth in United States Letters Patent No. 736,587, granted August 18, 1903, on application of Gano S. Dunn and Edwin E. Douglas. In conjunction with the development of the drum in Fig. i are four multiplevoltage leads a Z) 0 (Z and a motor M. lontacts are arranged for fifteen different posi- --tions with the motor running forward at this number of speeds and six different positions with the motor reversed at different speeds. The electrical connections effected at these different speeds are set forth in the abovementioned patent. As the precise character of the connections is not material to the invention herein set forth, they will not be described in detail. The invention is equally applicable to electric switches wherein the contacts and connections are arranged to effect changes of electrical connections for other purposes.

The switch-drum, as herein illustrated, has a central spindle A in the axisrzx :1; of the drum, to which a star-wheel B is pinned near one end and a cross-bar O is pinned near the opposite end. On opposite sides of the axis of the drum and parallel therewith are drawn steel rods D E, the ends of which are supported by the star-wheel and cross-bar and are pinned thereto, so that the parts enumerated form a rigid structure. The rods, which by reason of their eccentric positions will be termed side rods, are covered with sleeves F of insulating material. The contact- :arrying rings of the controller are the ring (it for eii'ecting lield changes by controlling resistance in the shunt field-circuit of the motor M, the two rings H H for effecting motor reversal and introducing additional breaks at the points where voltage changes are made, and two rings K K for effecting the multiple-voltage changes.

Each of the contact-rings is in two parts m 02, each of which may be defined as a semicontact-ring. In practice the rings are preferably cast whole, holes Z: 7:? are drilled to receive the side rods, holes are drilled and tapped for clamping-screws Z, and the rings are then sawed apart to form the semicontact-rings m at, the saw-cuts passing through the holes for the side rod, so that one semiring m will engage one side rod D on the side opposite to the axis of the drum and the other side rod E on the side facing the axis of the drum, and the other semiring a mating with the ring m will similarly engage the side rod E on the side opposite to the axis of the drum and the other side rod D on the side facing the axis of the drum. By this construction it will be seen that on removing the screws Which bind a pair of semirings together and clamp them to the side rods either semiring can be shifted, so as to disengage it from the side rods, and it can be removed without disturbing the mating semiring or any other parts of the drum.

hat I claim as new, and desire to secure by Letters Patent of the United States, is

1. An electric-switch drum comprising side rods and a series of contact-carrying rings each of which is clamped on both of the side rods, substantially as described.

2. An electric-switch drum comprisingtwo side rods and semicontact-rings each engaging with one side rod on the side facing the axis of the drum and engaging with the other side rod on the side opposite to the axis of the drum, and means for clamping the semicontact-rings to the side rods, substantially as described.

23. An electric-switch drum comprising two side rods and contact-rings each consisting of 

